Objective: The definition of the stressor criterion (DSM criterion A1) for posttraumatic stress disorder (PTSD) is hotly debated with major revisions being considered for DSM-5. We examine whether symptoms, course, and consequences of PTSD vary predictably with the type of stressful event that precipitates symptoms.

Method: We used data from the 2009 PTSD diagnostic subsample (N=3,013) of women from the Nurses’ Health Study II. We asked respondents about exposure to stressful events that qualified under DSM-III or DSM-IV or did not qualify under DSM criterion A1. Respondents selected the event they considered worst and reported subsequent PTSD symptoms. Among participants who met all other DSM-IV PTSD criteria, we compared distress, symptom severity, duration, impairment, receipt of professional help, and 9 physical, behavioral, and psychiatric sequelae (eg, physical functioning, unemployment, depression) by precipitating event group. Various assessment tools were used to determine fulfillment of PTSD criteria B through F and to assess these 14 outcomes.

Results: Participants with PTSD from DSM-III events reported, on average, 1 more symptom (DSM-III, mean=11.8 symptoms; DSM-IV, mean=10.7 [P<.001]; non-DSM, mean=10.9 [P<.01]) and more often reported that symptoms lasted 1 year or longer compared to participants with PTSD from other groups (DSM-III vs DSM-IV, P<.01; DSM-III vs non-DSM, P<.001). However, sequelae of PTSD did not vary systematically with precipitating event type.

Conclusions: Results indicate the stressor criterion as defined by the DSM may not be informative in characterizing PTSD symptoms and sequelae. In the context of ongoing DSM-5 revision, these results suggest that criterion A1 could be expanded in DSM-5 without much consequence for our understanding of PTSD phenomenology. Events not considered qualifying stressors under the DSM produced PTSD as consequential as PTSD following DSM-III events, suggesting PTSD may be an aberrantly severe but nonspecific stress response syndrome.